Fork carriage apparatus for a materials handling vehicle

Abstract

A materials handling vehicle is provided including a vehicle power unit, a monomast coupled to the vehicle power unit, and a fork carriage apparatus supported on the monomast. The fork carriage apparatus includes a mast carriage assembly directly coupled to the monomast for vertical movement, a fork carriage mechanism to which forks are mounted, and a reach mechanism coupled to the mast carriage assembly and to the fork carriage mechanism for actuating the fork carriage mechanism to move between an extended position and a retracted position.

What is claimed is: 
     
       1. A materials handling vehicle comprising:
 a vehicle power unit; 
 a monomast coupled to said vehicle power unit; and 
 a fork carriage apparatus supported on said monomast; 
 said fork carriage apparatus comprising:
 a mast carriage assembly including first and second side members movably coupled to said monomast, said mast carriage assembly including upper and lower elements connected to and extending between said side members at vertically opposing upper and lower ends of said side members, and at least one carriage frame member having opposing ends attached at an engagement location on each of said side members and extending laterally across a front side of said monomast and located in vertically spaced relation between said upper and lower ends; 
 a fork carriage mechanism to which forks are mounted; and 
 a reach mechanism coupled to and supported on said side members of said mast carriage assembly, and said reach mechanism coupled to said fork carriage mechanism for effecting movement of said fork carriage mechanism between an extended position and a retracted position, said reach mechanism including at least one laterally extending cross member which is located in vertically spaced relation and intersecting a common vertical plane with said carriage frame member, said vertical plane extending in front of and generally parallel to said monomast when said fork carriage mechanism is in said retracted position, wherein said carriage frame member extends laterally across said front side of said monomast at a fixed vertical location on said mast carriage assembly throughout movement of said fork carriage mechanism between said extended and retracted positions. 
 
 
     
     
       2. The materials handling vehicle as set out in  claim 1 , wherein said at least one carriage frame member comprises first and second carriage frame members extending laterally across said front side of said monomast in vertically spaced relation to said upper and lower ends of said mast carriage assembly, and said cross member is located between said first and second carriage frame members when said fork carriage mechanism is in said retracted position. 
     
     
       3. The materials handling vehicle as set out in  claim 1 , wherein said reach mechanism comprises a plurality of cross members and said carriage frame member is located between two of said cross members when said fork carriage mechanism is in said retracted position. 
     
     
       4. The materials handling vehicle as set out in  claim 3 , wherein said fork carriage mechanism includes at least one laterally extending fork frame member, and said fork frame member is located between said two cross members when said fork carriage mechanism is in said retracted position. 
     
     
       5. The materials handling vehicle as set out in  claim 1 , wherein said opposing ends of said at least one carriage frame member are non-detachably affixed to said engagement locations on said side members. 
     
     
       6. A materials handling vehicle comprising:
 a vehicle power unit; 
 a monomast comprising a first stage weldment coupled to said vehicle power unit, a second stage weldment positioned to telescope over said first stage weldment, and a third stage weldment positioned to telescope over said first and second stage weldments, said third stage weldment including opposing side surfaces, each side surface defining a vertically extending track; and 
 a fork carriage apparatus supported on said monomast; 
 said fork carriage apparatus comprising:
 a mast carriage assembly directly coupled to said third stage weldment for vertical movement relative to said monomast and including first and second side members supported on opposing sides of said third stage weldment, said mast carriage assembly including rollers supported to laterally inwardly facing sides of each of said first and second side members, said rollers being engaged in said tracks of said third stage weldment, both of said side surfaces of said third stage weldment located between said first and second side members; 
 a fork carriage mechanism to which forks are mounted; and 
 a reach mechanism including a scissors structure coupled to said mast carriage assembly and to said fork carriage mechanism for effecting movement of said fork carriage mechanism between an extended position and a retracted position, wherein said scissors structure of said reach mechanism comprises:
 first and second inner arms coupled to first and second outer arms; and 
 wherein said inner and outer arms extend substantially vertically and are in overlapping relationship over said laterally outwardly facing sides of said first and second side members when said fork carriage mechanism is in said retracted position; 
 
 
 wherein said monomast defines a longitudinal axis extending centrally between and parallel to said side members, and said first and second stage weldments each include a pair of members extending parallel to and on either side of said longitudinal axis, wherein said pairs of members of said first and second stage weldments are located closer to said longitudinal axis than said side members of said mast carriage assembly. 
 
     
     
       7. The materials handling vehicle as set out in  claim 6 , wherein said scissors structure of said reach mechanism comprises:
 each of said first and second inner arms includes a first end directly supported for movement along a vertical track in a respective one of said side members and a second end coupled to said fork carriage mechanism; and 
 each of said first and second outer arms includes a first end directly coupled at a pivot point to a respective one of said side members and a second end coupled to said fork carriage mechanism. 
 
     
     
       8. The materials handling vehicle as set out in  claim 7 , wherein said reach mechanism further includes a plurality of cross members extending between said first and second inner arms, and having lateral edges attached adjacent to front edges of said first and second inner arms to define an inner arm weldment. 
     
     
       9. The materials handling vehicle as set out in  claim 6 , wherein said rollers are located laterally inwardly from said laterally inwardly facing sides of said first and second side members.